Respectfully...
I have read a bunch of "use compression" and "use well applied effects", and "use analog tape" here.
I seen only I think two posts (sorry, I am not good at doing multiple "quotes") that really addressed the issue of making your recordings sound fuller.
It would be very important to remember this first and foremost about recordings:
Your electronic gear is going to make the least difference.
The quality and selection of your microphone is going to make the biggest difference on the front end (recording to "tape") and your monitors are going to make the biggest difference on the back end.
I will throw in too what John Sayers has been saying here lately, that you can have the best mic and best monitors in the world and it will sound like crap in a bad acoustic space.
So, you gotta have an appropriate mic for the application. You gotta have monitors that recreate the sound that mic is making. These are the two, and ONLY two mechanical conversions that happen in recording/playback, and for obvious reasons, they are the two most important things, along with a good room to record it in and to listen to it in.
After that, the quality of your preamps and A/D converters will make the next biggest differences. It is so sad to see so many people settling for low end in these two areas. Preamps are more important really because they are the place where the biggest gain change happens in the recording chain (aside from the monitor power amp, but power amps all in all are getting much cleaner with much better slew rates to move the bass.....). A/D conversion is far more important then many think. High resolution converters (20 or 24) means that the dithering (yes, dithering HAS to happen during the A/D conversion....the dithering for going from say 24 bits to 16 bits is called "redithering" technically) that happens in the A/D conversion is more detailed. Also, the quality of the chipset in the converter makes a huge difference. Many here may try to argue this, but until you have put an Apogee 16 bit converter against a cheaper converter, even at a higher bit resolution, you will never know the big difference there really is.
Next. Your mixing board is so important in your studio. It interfaces everything together. Studios are mostly built around the mixer it will house. Decision on what mic pre's and external eq's are put in the rack depend a lot on the house console. If you buy cheap here, you will be putting a lot of stuff in the rack to make up for it. Aside from that, the OP amps (or lack of them), the calibration of each channel strip, etc....on a nice mixer keep consistency in the sound, and allow to engineer to expect the very same results of any applied function from channel to channel.....Blah blah blah....
Unless you are using a turnkey type of DAW (ie. ProTool, Sonic Solutions, Sadie, Soundscape) you are making very big compromises in the quality of your mixing, dynamic, and effect processing. Hell, some engineers feel that the above systems are a compromise to sound quality, and they are worlds better then most of the riff raff you will find in the "budget" market.
So lets say you have your nice setup going. Great mics, great monitors, great room, competent mixing and dynamic/effect processing.
Who is to say you would have a good sound GETTING to that great setup? Who is to say that the part that is being played is appropriate to the song? Who is to say it is in tune? (I cannot count how many intonation problems I have heard on budget demo's!!!)
It really starts with a good song, like was stated earlier. Then, you need to have some good players playing the parts. Those good players really need to have some good tone going on. THEN, you need the nice recording setup to make it all fly. Aside from all that, you need to have engineering experience that can keep the tracks handled properly throughout the whole process. A great engineer is soooooooooo helpful. A great PRODUCER is so helpful. Blah blah blah......
I find it funny that dudes who have never spent a significant amount of money on a project in a competent studio want to buy $5000 worth of recording gear and make recordings that sound like they were done in a million dollar studio with ace engineers and a top name producer!!!! I find that beyond unrealitic.
Friend, if you want fuller sounding recordings, get at least one signal chain of some class A gear (preferably two, you might want to mic something stereo...
) and spend your time playing around with getting exactly the sound you want on tape with no applied processing (eq, compression, gates). Once you get that far, THEN give a little "to tape" compression a try, cause I will admit to using it myself, but in very light dosages unless the artist is just simply lousy, then the whole recording is compromises anyway, so who cares if the damn bass is pumping and breathing!
A friend of mine just finished a 7 song CD he co-produced, engineered, and played guitar on in his studio. He houses a Yamaha O2R console with 20 bit ADAT's, some Focusrite Red pre's, Drawmer pre's, Joe Meek pre's, Neumann U87's, a 414, 4050, 4033, ADK tube mic, etc.......
His product didn't have the normal time restraints because he was working the producing part on "spec", so the whole of the budget (he slashed his studio rate in addition for this artist) was dedicated to production. It was mastered in a facility with very very top of the line gear with an engineer who has mastered several major label releases....blah blah blah.....
You know what? With all that time spent and all that "seemingly" nice gear, it still just sounded like a very fine sounding demo! The musicians involved have been recording artists for years, and the producing was very well done. 32 tracks!!! They used them up in every song. Very tasteful decisions made. But it still lacked "that sound". It was "full" but not "deep". It had "detail" but it lacked "prettiness" in the highs.
The faults? Bad recordings room. Bad mixing room. Bad mixer.
This dude's studio is worth around $100k! The engineer has a world of experience. It would seem that they could have kicked out a "radio ready" mix with this stuff. Just didn't happen. Personally, the recording is nice to listen to, but it still doesn't have to richness and clarity of a big time recording, even though these guys did it all right. They just lacked great rooms and a great console to bring it all together. I felt too that the mic selection was a bit weak. Variety is key here.
So, that is what I think about getting "fuller sounding mixes". Friend, you are using a recording medium that uses data compression! You probably don't have single piece of gear that you would see at the Record Plant or Paisley Park.
Good luck competing with the sounds those two fine studios will kick out.
Get the sound you want to tape. You DON'T have gear good enough to manipulate it enough after the fact.
Gosh, this is long. Sorry. I am sure though that a few of you will have a merry time slapping me around for this post.
Good Day!